mirror/guile
mirror/guile
1
Fork 0
mirror of https://git.savannah.gnu.org/git/guile.git synced 2025-06-18 01:30:27 +02:00
Code Activity

Add SCM_LIKELY and SCM_UNLIKELY for optimization

Browse source 
* libguile/numbers.c (scm_abs, scm_quotient, scm_remainder, scm_modulo):
  Add SCM_LIKELY and SCM_UNLIKELY in several places for optimization.

  (scm_remainder): Add comment about C99 "%" semantics.
  Strip away a redundant set of braces.
This commit is contained in:
Mark H Weaver 2011-01-28 23:58:02 -05:00 • committed by Andy Wingo
parent 074c414e29
commit a16982ca4f
1 changed files with 33 additions and 32 deletions
Download patch file Download diff file Expand all files Collapse all files

65
libguile/numbers.c
View file

@ -774,18 +774,18 @@ SCM_GPROC (s_quotient, "quotient", 2, 0, 0, scm_quotient, g_quotient);
SCM SCM
scm_quotient (SCM x, SCM y) scm_quotient (SCM x, SCM y)
{ {
if (SCM_I_INUMP (x)) if (SCM_LIKELY (SCM_I_INUMP (x)))
{ {
scm_t_inum xx = SCM_I_INUM (x); scm_t_inum xx = SCM_I_INUM (x);
if (SCM_I_INUMP (y)) if (SCM_LIKELY (SCM_I_INUMP (y)))
{ {
scm_t_inum yy = SCM_I_INUM (y); scm_t_inum yy = SCM_I_INUM (y);
if (yy == 0) if (SCM_UNLIKELY (yy == 0))
scm_num_overflow (s_quotient); scm_num_overflow (s_quotient);
else else
{ {
scm_t_inum z = xx / yy; scm_t_inum z = xx / yy;
if (SCM_FIXABLE (z)) if (SCM_LIKELY (SCM_FIXABLE (z)))
return SCM_I_MAKINUM (z); return SCM_I_MAKINUM (z);
else else
return scm_i_inum2big (z); return scm_i_inum2big (z);
@ -809,12 +809,12 @@ scm_quotient (SCM x, SCM y)
} }
else if (SCM_BIGP (x)) else if (SCM_BIGP (x))
{ {
if (SCM_I_INUMP (y)) if (SCM_LIKELY (SCM_I_INUMP (y)))
{ {
scm_t_inum yy = SCM_I_INUM (y); scm_t_inum yy = SCM_I_INUM (y);
if (yy == 0) if (SCM_UNLIKELY (yy == 0))
scm_num_overflow (s_quotient); scm_num_overflow (s_quotient);
else if (yy == 1) else if (SCM_UNLIKELY (yy == 1))
return x; return x;
else else
{ {
@ -858,15 +858,18 @@ SCM_GPROC (s_remainder, "remainder", 2, 0, 0, scm_remainder, g_remainder);
SCM SCM
scm_remainder (SCM x, SCM y) scm_remainder (SCM x, SCM y)
{ {
if (SCM_I_INUMP (x)) if (SCM_LIKELY (SCM_I_INUMP (x)))
{ {
if (SCM_I_INUMP (y)) if (SCM_LIKELY (SCM_I_INUMP (y)))
{ {
scm_t_inum yy = SCM_I_INUM (y); scm_t_inum yy = SCM_I_INUM (y);
if (yy == 0) if (SCM_UNLIKELY (yy == 0))
scm_num_overflow (s_remainder); scm_num_overflow (s_remainder);
else else
{ {
/* C99 specifies that "%" is the remainder corresponding to a
quotient rounded towards zero, and that's also traditional
for machine division, so z here should be well defined. */
scm_t_inum z = SCM_I_INUM (x) % yy; scm_t_inum z = SCM_I_INUM (x) % yy;
return SCM_I_MAKINUM (z); return SCM_I_MAKINUM (z);
} }
@ -889,10 +892,10 @@ scm_remainder (SCM x, SCM y)
} }
else if (SCM_BIGP (x)) else if (SCM_BIGP (x))
{ {
if (SCM_I_INUMP (y)) if (SCM_LIKELY (SCM_I_INUMP (y)))
{ {
scm_t_inum yy = SCM_I_INUM (y); scm_t_inum yy = SCM_I_INUM (y);
if (yy == 0) if (SCM_UNLIKELY (yy == 0))
scm_num_overflow (s_remainder); scm_num_overflow (s_remainder);
else else
{ {
@ -931,13 +934,13 @@ SCM_GPROC (s_modulo, "modulo", 2, 0, 0, scm_modulo, g_modulo);
SCM SCM
scm_modulo (SCM x, SCM y) scm_modulo (SCM x, SCM y)
{ {
if (SCM_I_INUMP (x)) if (SCM_LIKELY (SCM_I_INUMP (x)))
{ {
scm_t_inum xx = SCM_I_INUM (x); scm_t_inum xx = SCM_I_INUM (x);
if (SCM_I_INUMP (y)) if (SCM_LIKELY (SCM_I_INUMP (y)))
{ {
scm_t_inum yy = SCM_I_INUM (y); scm_t_inum yy = SCM_I_INUM (y);
if (yy == 0) if (SCM_UNLIKELY (yy == 0))
scm_num_overflow (s_modulo); scm_num_overflow (s_modulo);
else else
{ {
@ -1008,10 +1011,10 @@ scm_modulo (SCM x, SCM y)
} }
else if (SCM_BIGP (x)) else if (SCM_BIGP (x))
{ {
if (SCM_I_INUMP (y)) if (SCM_LIKELY (SCM_I_INUMP (y)))
{ {
scm_t_inum yy = SCM_I_INUM (y); scm_t_inum yy = SCM_I_INUM (y);
if (yy == 0) if (SCM_UNLIKELY (yy == 0))
scm_num_overflow (s_modulo); scm_num_overflow (s_modulo);
else else
{ {
@ -1029,22 +1032,20 @@ scm_modulo (SCM x, SCM y)
} }
else if (SCM_BIGP (y)) else if (SCM_BIGP (y))
{ {
{ SCM result = scm_i_mkbig ();
SCM result = scm_i_mkbig (); int y_sgn = mpz_sgn (SCM_I_BIG_MPZ (y));
int y_sgn = mpz_sgn (SCM_I_BIG_MPZ (y)); SCM pos_y = scm_i_clonebig (y, y_sgn >= 0);
SCM pos_y = scm_i_clonebig (y, y_sgn >= 0); mpz_mod (SCM_I_BIG_MPZ (result),
mpz_mod (SCM_I_BIG_MPZ (result), SCM_I_BIG_MPZ (x),
SCM_I_BIG_MPZ (x), SCM_I_BIG_MPZ (pos_y));
SCM_I_BIG_MPZ (pos_y));
scm_remember_upto_here_1 (x); scm_remember_upto_here_1 (x);
if ((y_sgn < 0) && (mpz_sgn (SCM_I_BIG_MPZ (result)) != 0)) if ((y_sgn < 0) && (mpz_sgn (SCM_I_BIG_MPZ (result)) != 0))
mpz_add (SCM_I_BIG_MPZ (result), mpz_add (SCM_I_BIG_MPZ (result),
SCM_I_BIG_MPZ (y), SCM_I_BIG_MPZ (y),
SCM_I_BIG_MPZ (result)); SCM_I_BIG_MPZ (result));
scm_remember_upto_here_2 (y, pos_y); scm_remember_upto_here_2 (y, pos_y);
return scm_i_normbig (result); return scm_i_normbig (result);
}
} }
else else
SCM_WTA_DISPATCH_2 (g_modulo, x, y, SCM_ARG2, s_modulo); SCM_WTA_DISPATCH_2 (g_modulo, x, y, SCM_ARG2, s_modulo);